A non-volatile memory device may maintain data stored therein even when a power supply is no longer provided. A flash memory device is an example of the non-volatile memory device and may include a memory cell in which data may be electrically written or erased, and the memory cell may include a floating gate transistor. The memory cell may store data by adjusting a threshold voltage of the floating gate transistor.
The threshold voltage of the floating gate transistor may be changed when a high voltage is applied to a gate of the floating gate transistor. The floating gate transistor of the memory cell may be connected to a word line, and the threshold voltage of the floating gate transistor may be changed by a voltage that is applied to the word line.